1. Field of the Invention
The present invention relates to scan systems, such as those using scanning electron microscope (SEM) or atomic force microscopy (AFM). In particular, the present invention relates to how to build a fast scan system.
2. Discussion of the Related Art
In a conventional scan system (e.g., SEM, scanning tunneling microscope (STM), AFM, magnetic force microscopy (MFM), single-dish radio telescopes, scanning radar system, or a scanning laser Doppler system), a scanner scans the target line-by-line. Often the scan time is so long that it requires a lot of resources (e.g., money, energy) to run such a scanner. In some other case, since the scan time is long, it is difficult to scan a dynamically changing target.